KVM: arm64: Save guest's ZCR_EL1 before saving the FPSIMD state

mainline inclusion
from mainline-v5.13-rc1
commit b145a843
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8E73O
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b145a8437aab2799969f6ad8e384b557872333c2



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Make sure the guest's ZCR_EL1 is saved before we save/flush the
state. This will be useful in later patches.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>